from flask import Flask, render_template, Response,request
import cv2


class VideoCamera(object):
    def __init__(self,name):
        # 通过opencv获取实时视频流
        self.video = cv2.VideoCapture("rtsp://36.133.66.40:8554/"+name)

    def __del__(self):
        self.video.release()

    def get_frame(self):
        success, image = self.video.read()
        # 因为opencv读取的图片并非jpeg格式，因此要用motion JPEG模式需要先将图片转码成jpg格式图片
        if len(image) > 0:
            ret, jpeg = cv2.imencode('.jpg', image)
            return jpeg.tobytes()
        else:
            return True


app = Flask(__name__)

@app.route('/')
def index():
    # jinja2模板，具体格式保存在index.html文件中
    return render_template('display.html')


def gen(camera):
    while True:
        frame = camera.get_frame()
        # 使用generator函数输出视频流， 每次请求输出的content类型是image/jpeg
        yield (b'--frame\r\n'
               b'Content-Type: image/jpeg\r\n\r\n' + frame + b'\r\n\r\n')


@app.route('/video_feed')  # 这个地址返回视频流响应
def video_feed():
    try:
        name = request.args.get("name","")
        return Response(gen(VideoCamera(name)),mimetype='multipart/x-mixed-replace; boundary=frame')
    except:
        pass


if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)
